Ton Schumacher

For colon cancer that is mismatch-repair deficient (about 10-15% of colon cancers, more in older patients), a single short course of immunotherapy before surgery is now a reasonable standard and is far more effective than chemotherapy, which barely works in this subtype. It requires testing every colon cancer for mismatch repair at diagnosis, before surgery. Whether some patients can safely skip surgery, as in dMMR rectal cancer, is the next question.

NICHE-2 shows that a month of immunotherapy before surgery can effectively cure locally advanced dMMR colon cancer, where chemotherapy after surgery has limited benefit. It is changing guidelines towards neoadjuvant checkpoint blockade for this group and raises the question of whether surgery can be omitted altogether, as in dMMR rectal cancer. Whether the same applies to MMR-proficient tumours is being tested but is not established.

This trial supplied the randomised proof that was missing for TIL therapy and showed academic centres can run cell-therapy phase 3 trials without industry. It supports TIL as a standard option after checkpoint inhibitor failure in melanoma and underpinned reimbursement in the Netherlands. The comparator, ipilimumab, is itself only modestly effective in this setting, and overall survival did not differ significantly.